CONTROLLING A POWER OF AN ELECTRICAL MOTOR

摘要

A motor control circuit (MC) comprising input terminals (ITl, IT2) to receive a rectified input voltage (Vrm), and output terminals (OTl, 0T2) to supply a motor drive signal (Vm). A switching circuit (1) is alternately in an on- state (Ton) and an off- state (Toff) for intermittently coupling the input terminals (ITl, IT2) to the output terminals (OTl, 0T2). A controller (2) controls the switching circuit (1) to be (i) in the on- state (Ton) during a first period in time (Tl) when an amount of magnetic saturation of the motor is smaller than a predetermined value, and (ii) alternately in the on-state (Ton) and the off-state (Toff) to obtain a pulse width control of the motor drive signal (Vm) during a second period in time (T2) when the amount of magnetic saturation of the motor is larger than the predetermined value.